Printing press



M. S. THOMAS PRINTING PRESS July 27, 1937.

Filed June 10, 1935 miss .55.

Patented July 27, 1937 UNITED STATES PATENT OFFICE PRINTING PREss MarkStThomas, Green Bay, Wis. Application Jane 10, 1935, Serial No. 25,913 r3 Claims (01. 101-228) This invention relates to printing presses of thecontinuous web rotary type and has for an object to provide novel meansfor varying the surface speed of the plate cylinder relatively to thesurface speed of the tympan roll between printings to effect, a.predetermined spacing between printed impressions.

The invention generally comprises plate cylinder advancing or retardingmeans operable between the printings to vary the speed ratio of theplate cylinder relatively to the tympanroll, and quiescent during theprintings to permit the plate cylinder to have identical surface speedrelatively to the tympan roll.

The invention includes specifically a diiferential gear drive for theplate cylinder controlled by a cam to speed up or retard the platecylinder to a predetermined speed ratio relatively to the tympan rollbetween printings.

With the above and other objects in view the invention consists ofcertain novel details of construction and combinations of partshereinafter fully described and claimed, it being understood thatvarious modifications may be resorted to within the scope of theappended claims without departing from the spirit or sacrificing any ofthe advantages of the invention.

In the accompanying drawing forming part of this specification,

Figure 1 is a front elevation partly in section of a web printing rotarypress constructed in accordance with the invention.

Figure 2 is a detail cross sectional View taken on the line 22 of Figure1.

Referring now to the drawing in which like characters of referencedesignate similar parts in the various views, l0 designates a tympanroll and Il designates a plate cylinder, the plate cylinder in thisinstance being shown as the same in diameter as the tympan roll so thatordinarily it would make one revolution for each impression or printingand spacing. The tympan roll and the plate cylinder are mounted inframes l2 and rotatable on journal boxes I3.

The plate cylinder II is loosely mounted on a shaft 14 which is providedwith bearings l4 disposed concentrically in the journal boxes I3 of theplate cylinder. At one end of the shaft I4 is a drive l5 of equal ratioto the diameters of the tympan roll and plate cylinder and in thepresent instance this drive is shown as a belt gear device ofconvention-a1 type. The opposite end of the driven shaft I4 is connectedto the loose plate cylinder by a difierential gear mechanism whereby thespeed of the cylinder may be advanced or retarded relatively to thespeed of the shaft as will nowbe described. The differential gearmechanism'comprises a gear I! which is fixed on the hub of the platecylinder H and meshes witha difierential pinion !8 which is mounted on aspider l9 and in turn'meshes with a gear 2ll. The'gears l1, l8 v and 20are'housed within a gear case 16 having formed integral therewith aring-gear 2! which meshes with ai gear 22 fixed to the'shaft 23 10 ofthe tympan roll 18;- -'Ihe"gearratio between the ring gear' 2! and-drivegear- 22 isthe same ratio as the drive 15 on the opposite side of theroll.

The end of the driven shaft I4 is provided with 15 splines 24 over whichis slidably fitted a sleeve 25 the bore of which is splined to interfitwith the splines 24 so that the sleeve is confined to reciprocatorymovement longitudinally of the end of the shaft Hi. The outer surface ofthe 20 sleeve is provided with helical splines 26 which interfit withsimilar splines 21 formed in the hub of the gear 20. The outer end ofthe sleeve is uniformly re-, duced and mounted thereon is an annulus. 28which projects into the groove of a cam 29 that may be rotated by anyconvenient rotating part of the printing press to oscillate the sleeve25 inwardly or outwardly upon the splined end 24 of the shaft, accordingto the pitch of the cam 30 groove. Cams of various pitches may beinterchanged with the cam 29 to confine the throw or travel of thesleeve 25 to predetermined limits. The plate 30 is fastened to thesurface of the plate cylinder in the conventional manner. If only oneplate is used then onlyone impression can be made with one revolution ofthe cylinder. This means that the plate will register with the tympanroll once during each revolution and the distance between printedimpressions 32 on 40 the web 3| will be equal to the circumference ofthe plate cylinder. Now assume that this distance should be greater orless than the circumference of the plate cylinder. A cam 29 is selectedwhich will move the annulus 28 to the 45 right or left to apredetermined extent. This moves the sleeve 25 in the hub 21 of thegear20 and by virtue of the interengaging spiral splines of the gear andsleeve, the gear 20 ,is speeded up or retarded as the case may be. Thismovement is transmitted through the planetary gear l8 to the side gearI! and the latter will be speeded up or retarded accordingly, and beingfixed to the hub of the plate cylinder, will drive the plate cylinder ata greater or less 55 speed relatively to the tympan roll than would bethe case if the plate cylinder were constantly driven at true gear ratiospeed. During the impression or printing time, the tympan roll is, ofcourse, running at the surface speed of the web being printed and at thesame identical surface speed as the'plate cylinder H and at this timethe cam is at one limit of movement or at a position of rest so far asthe sleeve 25 is concerned so that the differential gears 20 and I! aremoving as a unit at the identical speed of the shaft I4 and gear drivel5. Only between printings is the differential gear drive operated tovary the speed of the plate cylinder I l relatively to the tympan roll.I0. It will be pointed out moreover that the printing or impressioncylinder may be advanced during at least one revolution of the cylinderso as to shorten the space between the next printing. If desired, analternate short and long printing may be had, or one impression, namely,the long impression may be skipped. Where the splines are so arranged asto retard the impression cylinder the longer printing may be used andthe shorter printing skipped.

The cam and splines therefore constitute periodically actuated means foralternately advancing and retarding the plate cylinderrelative to thetympan; roll.

From the above description it is thought that the construction andoperation of my invention will be fully understood without furtherexplanation.

What is claimed is:

1. In a web printing rotary press, a plate cylinder, a tympan roll,means for rotating the cylinder and roll at equal surface speeds, saidmeans including a difierential gear, splined means associated with saidgear, and cam operating means for periodically reciprocating saidsplined means, said splined means upon movement in one directionadvancing .said cylinder relative to said roll, movement of the splinedmeans in the opposite direction returning said cylinder to its originalposition relative to said roll.

2. In a web printing rotary press, a plate cylinder, a tympan roll,means for rotating the cylinder and roll at equal surface speeds, saidmeans including a differential gear, splined means operatively connectedto said differential gear, cam means, and means carried by said splinedmeans engaging said cam means for periodically reciprocating saidsplined means, movement of said splined means in one direction advancingsaid cylinder relative to said roll, and movement of said splined meansin the 0pposite direction retarding said cylinder relative to the roll.

3. In a web printing rotary press, a plate cylinder, a tympan roll,means for rotating the cylinder and roll at equal surface speeds, andperiodically actuated means for alternately advancing and retarding saidcylinder relative to said roll.

MARK S. THOMAS.

